Reaction kettle device for synthesizing molecular sieve crystals

Abstract

The utility model discloses a reaction kettle device based on molecular sieve crystallization synthesis relates to the field of molecular sieve crystallization synthesis, and its technical scheme main points are: including: anchor, the anchor fixed mounting in the bottom of stirring shaft, and the anchor with the inner bottom surface of reaction kettle body is adapted, is used for the radial mixing of crystallization slurry of reaction kettle body bottom, trilobal paddle, trilobal paddle fixed mounting in the stirring shaft is located the upper region of anchor, is used for the axial mixing of crystallization slurry of reaction kettle body in upper and lower layers, effect is through the radial mixing of anchor and the axial mixing of trilobal paddle synergistic effect, completely overcome the deficiency that only single direction mixing of existing SSZ - 13 molecular sieve crystallization kettle stirring mechanism, make the crystallization slurry in the reaction kettle body 1 realize global uniform mixing, avoid the formation " a small amount of single crystal big granule " in the crystallization process, ensure that the SSZ - 13 molecular sieve prepared has the catalytic performance satisfying the catalytic performance of automobile exhaust high -efficient processing demand.

Description

Technical Field

[0001] This utility model relates to the field of molecular sieve crystallization synthesis, and more specifically, it relates to a reaction vessel device based on molecular sieve crystallization synthesis. Background Technology

[0002] In the field of automotive exhaust treatment, nitrogen oxides (NOx) x NO is one of the main pollutants and needs to be catalytically converted into non-toxic and harmless nitrogen before it can be emitted. SSZ-13 molecular sieve is the core material for this catalytic process. When automobile exhaust flows through a honeycomb carrier coated with SSZ-13 molecular sieve, SSZ-13 can catalyze the release of NO. x It is converted into nitrogen gas, so its catalytic performance directly determines the treatment efficiency of automobile exhaust.

[0003] The catalytic performance of SSZ-13 molecular sieve is closely related to its microscopic particle size: the smaller the particle size, the larger the specific surface area of ​​the molecular sieve, and the better its catalytic performance with NO. x The larger the contact area, the stronger the catalytic activity; if the particles are too large, the catalytic efficiency will decrease significantly. To prepare small-particle SSZ-13, the key is that the crystallization process needs to be fully stirred to form "turbulence" in the crystallization slurry. The intense disturbance of the turbulence is used to inhibit the excessive growth of crystal nuclei (to avoid the aggregation of crystal nuclei to form large particles).

[0004] However, the crystallization vessel used for crystallization of existing SSZ-13 molecular sieves has obvious defects: its stirring mechanism can only achieve "one-way" mixing (such as stirring only radially or only axially), resulting in poor mixing effect; for example, radial stirring only will lead to uneven mixing of the upper and lower layers of slurry in the vessel, and axial stirring only will lead to insufficient mixing of the slurry at the edge and center of the vessel. Ultimately, the crystallized molecular sieve is prone to forming "a small number of large single crystal particles", and its catalytic performance cannot meet the requirements of efficient treatment of automobile exhaust. This is the core problem that the existing technology urgently needs to solve.

[0005] Therefore, in order to solve the above-mentioned technical problems, this application proposes a reaction vessel device based on molecular sieve crystallization synthesis. Utility Model Content

[0006] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a reaction vessel device based on molecular sieve crystallization synthesis.

[0007] To achieve the above objectives, this utility model provides the following technical solution: a reaction vessel apparatus based on molecular sieve crystallization synthesis, comprising: The reactor body is used to contain molecular sieve crystallization slurry; A stirring shaft is vertically disposed inside the reactor body, and the top end of the stirring shaft extends out of the reactor body to connect to the drive mechanism. An anchor paddle, which is fixedly installed at the bottom end of the stirring shaft and is adapted to the inner bottom surface of the reactor body, is used to radially mix the crystallized slurry at the bottom of the reactor body. The three-bladed impeller is fixedly installed above the stirring shaft in the area above the anchor impeller, and is used to axially mix the crystallized slurry in the upper and lower layers of the reactor body.

[0008] Preferably, a baffle plate is fixedly connected to the inner wall of the reactor body. There are four baffle plates in total, which are evenly distributed along the circumference of the reactor body. They are used to cause the crystallized slurry to bounce back during the stirring process to enhance the intensity of stirring.

[0009] Preferably, the three blades of the three-bladed impeller are evenly distributed at an angle of °, and the plane containing the blades of the three-bladed impeller is perpendicular to the axis of the stirring shaft.

[0010] Preferably, the length of the stirring shaft is adjustable.

[0011] Preferably, the stirring shaft includes a connecting part connected to the drive mechanism, the bottom end of the connecting part is connected to the stirring rod through an adjusting part, and the anchor paddle and the three-bladed paddle are mounted on the stirring rod.

[0012] Preferably, the adjusting part includes vertical plates fixed to both sides of the bottom end of the connecting part, and a screw fixed to the top end of the stirring rod. A circular plate is fixedly connected to the bottom end of the vertical plate, and a through hole for the screw to pass through is opened in the center of the circular plate. Nuts are threadedly connected to the outer side wall of the screw on both the upper and lower sides of the circular plate.

[0013] Preferably, guide rails are fixedly connected to the opposite surfaces of the two vertical plates, a top plate is fixedly connected to the top of the screw, and both sides of the top plate are slidably connected to the guide rails by sliders.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. This utility model completely overcomes the shortcomings of the existing SSZ-13 molecular sieve crystallization vessel stirring mechanism, which can only mix in one direction, by using the synergistic effect of radial mixing of the anchor paddle and axial mixing of the three-bladed paddle. This enables the crystallization slurry in the reactor body to achieve uniform mixing throughout the entire process, avoiding the formation of "a small number of large single crystal particles" during crystallization. This ensures that the prepared SSZ-13 molecular sieve has the catalytic performance to meet the requirements of efficient treatment of automobile exhaust, thus solving the problems in the background technology. 2. This utility model uses baffles to form a stable blocking and rebound effect on the crystallized slurry during the stirring process from four evenly distributed positions around the circumference of the reactor body. This not only avoids the dead corner problem of undisturbed slurry flow and insufficient mixing caused by insufficient number or uneven distribution of baffles, but also allows the slurry driven by the radial mixing of the anchor paddle and the axial mixing of the three-bladed paddle to form multi-directional collisions and disturbances through multi-directional rebound, further breaking the limitation of a single flow direction and significantly enhancing the intensity of stirring. 3. This utility model can flexibly adjust the distance between the anchor paddle and the bottom surface of the reactor body and the axial position of the three-bladed paddle in the reactor body according to the actual liquid level of the SSZ-13 molecular sieve crystallization slurry in the reactor body and the stirring depth requirements of different batches of crystallization processes. This avoids the problem of the anchor paddle not being able to effectively stir the bottom slurry when the slurry level is low due to the fixed stirring shaft length, or the three-bladed paddle not being able to cover the upper slurry when the slurry level is high, resulting in a mixing dead zone. 4. This utility model provides precise guidance for the screw's up-and-down movement through the slider, guide rail, and top plate, avoiding the screw's deviation and shaking problems that may occur due to the limitation of the circular plate through hole alone. It ensures that the stirring rod drives the anchor paddle and the three-bladed paddle to maintain a straight trajectory when moving up and down, preventing the anchor paddle from deviating and rubbing against the bottom surface of the reactor or causing stirring dead corners. It also prevents the three-bladed paddle from deviating and failing to evenly cover the axial area of ​​the slurry, thus affecting the mixing effect. Attached Figure Description

[0015] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This utility model Figure 1 Another perspective on the specific structure; Figure 3 This is a schematic diagram of the specific structure when the length of the stirring shaft is fixed in this utility model; Figure 4 This utility model Figure 3 Enlarged view of the local structure of A; Figure 5 This is a schematic diagram of the specific structure when the length of the stirring shaft in this utility model is not fixed. In the diagram: 1. Reactor body; 2. Stirring shaft; 201. Connecting part; 202. Adjusting part; 2021. Vertical plate; 2022. Screw; 2023. Circular plate; 20231. Through hole; 2024. Nut; 2025. Guide rail; 2026. Top plate; 2027. Slider; 203. Stirring rod; 3. Anchor propeller; 4. Three-bladed propeller; 5. Baffle plate. Detailed Implementation

[0016] like Figure 1-5 As shown, this utility model provides a reaction vessel apparatus for molecular sieve crystallization synthesis, comprising: Reactor body 1, which is used to contain molecular sieve crystallization slurry; Stirring shaft 2 is vertically installed inside the reactor body 1, and the top end of stirring shaft 2 extends out of the reactor body 1 to connect to the drive mechanism. Anchor 3 is fixedly installed at the bottom end of the stirring shaft 2, and the anchor 3 is adapted to the inner bottom surface of the reactor body 1, and is used to radially mix the crystallized slurry at the bottom of the reactor body 1. The three-bladed propeller 4 is fixedly installed on the stirring shaft 2 above the anchor propeller 3. It is used to axially mix the crystallized slurry in the upper and lower layers of the reactor body 1. The three blades of the three-bladed propeller 4 are evenly distributed at an angle of 120°, and the plane of the blades of the three-bladed propeller 4 is perpendicular to the axis of the stirring shaft 2. The baffle plate 5 is fixedly connected to the inner wall of the reactor body 1 and is used to cause the crystallized slurry to bounce back during the stirring process to enhance the intensity of stirring.

[0017] When the reactor is in operation, the slurry required for the crystallization of SSZ-13 molecular sieve is first injected into the reactor body 1. The external drive mechanism transmits driving force through the stirring shaft 2 extending from the top of the reactor body 1, causing the stirring shaft 2 to rotate stably. As the stirring shaft 2 rotates, the anchor blade 3, whose bottom end is adapted to the bottom surface of the reactor body 1, pushes the crystallization slurry at the bottom of the reactor to mix thoroughly in the radial direction due to its large contact area, avoiding the deposition of slurry at the bottom. At the same time, the three-bladed blade 4 located above the anchor blade 3 on the stirring shaft 2 rotates together with the stirring shaft 2, and pushes the crystallization slurry at the bottom of the reactor to mix thoroughly in the radial direction through its own blade structure. The crystallization slurry in the upper and lower layers of the reactor body 1 is efficiently mixed axially to overcome the defect of uneven mixing of the upper and lower layers of slurry caused by the existing radial stirring only. Finally, through the synergistic effect of the radial mixing of the anchor paddle 3 and the axial mixing of the three-bladed paddle 4, the deficiency of the existing SSZ-13 molecular sieve crystallization reactor stirring mechanism, which can only mix in one direction, is completely overcome. This enables the crystallization slurry in the reactor body 1 to achieve uniform mixing throughout the entire process, avoids the formation of "a small number of large single crystal particles" during crystallization, and ensures that the prepared SSZ-13 molecular sieve has the catalytic performance to meet the requirements of efficient treatment of automobile exhaust.

[0018] Furthermore, baffles 5 are fixedly connected to the inner wall of the reactor body 1. There are four baffles 5 in total, which are evenly distributed along the circumference of the reactor body 1. The baffles 5 can form a stable blocking and rebound effect on the crystallized slurry during the stirring process from four evenly distributed positions around the circumference of the reactor body 1. This not only avoids the dead corner problem of undisturbed slurry flow and insufficient mixing caused by insufficient number or uneven distribution of baffles 5, but also allows the slurry driven by the radial mixing of the anchor paddle 3 and the axial mixing of the three-bladed paddle 4 to form multi-directional collisions and disturbances through multi-directional rebound, further breaking the limitation of a single flow direction and significantly enhancing the intensity of stirring.

[0019] Finally, this invention also designs the length of the stirring shaft 2 to be adjustable (the height of the stirring shaft 2 and the anchor paddle 3 can be adjusted simultaneously). According to the actual liquid level of the SSZ-13 molecular sieve crystallization slurry in the reactor body 1 and the stirring depth requirements of different batches of crystallization processes, the distance between the anchor paddle 3 and the bottom surface of the reactor body 1 and the axial position of the three-bladed paddle 4 in the reactor body 1 can be flexibly adjusted. This avoids the problem of the anchor paddle 3 not being able to effectively stir the bottom slurry when the slurry level is low due to the fixed length of the stirring shaft 2, or the three-bladed paddle 4 not being able to cover the upper slurry when the slurry level is high, resulting in a mixing dead zone.

[0020] The following is the specific structure of the stirring shaft 2: The stirring shaft 2 includes a connecting part 201 connected to the drive mechanism. The bottom end of the connecting part 201 is connected to the stirring rod 203 through the adjusting part 202. The anchor paddle 3 and the three-bladed paddle 4 are installed on the stirring rod 203. The adjusting part 202 includes vertical plates 2021 fixed on both sides of the bottom end of the connecting part 201 and a screw 2022 fixed on the top end of the stirring rod 203. A circular plate 2023 is fixedly connected to the bottom end of the vertical plate 2021, and a through hole 20231 for the screw 2022 to pass through is opened in the center of the circular plate 2023. Nuts 2024 are threadedly connected to the outer side wall of the screw 2022 on both the upper and lower sides of the circular plate 2023.

[0021] When adjusting the height, first loosen the nut 2024 above the circular plate 2023 in the adjusting part 202, and then loosen the nut 2024 below the circular plate 2023. This releases the screw 2022, which was originally clamped and fixed by the upper and lower nuts 2024, allowing the screw 2022 to move up and down along the through hole 20231 in the center of the circular plate 2023. Subsequently, according to the liquid level of the crystallization slurry in the reactor body 1 or the required positions of the anchor paddle 3 and the three-bladed paddle 4, push the stirring rod 203 up or down, causing the screw 2022 to move up and down along the through hole. Move 20231 until the distance between the anchor paddle 3 and the bottom surface of the reactor and the position of the three-bladed paddle 4 in the slurry reach the expected requirements; finally, first tighten the nut 2024 below the circular plate 2023 to make it fit tightly against the bottom surface of the circular plate 2023 to achieve initial fixation, then tighten the nut 2024 above the circular plate 2023. Through the clamping action of the upper and lower nuts 2024 on the circular plate 2023, the screw 2022 and the stirring rod 203 are stably fixed at the adjusted height, thus completing the adjustment of the length of the stirring shaft 2 and the height of the anchor paddle 3 and the three-bladed paddle 4.

[0022] Furthermore, guide rails 2025 are fixedly connected to the opposite surfaces of the two vertical plates 2021, and a top plate 2026 is fixedly connected to the top of the screw 2022. Both sides of the top plate 2026 are slidably connected to the guide rails 2025 via sliders 2027. That is, when the screw 2022 moves up and down, it drives the sliders 2027 to move up and down via the top plate 2026. The sliders 2027 slide linearly up and down along the guide rails 2025. This provides precise guidance for the up and down movement of the screw 2022, avoiding the potential deviation and wobbling of the screw 2022 that might occur if only the through hole 20231 of the circular plate 2023 is used for limiting. The stirring rod 203 ensures that the anchor paddle 3 and the three-bladed paddle 4 maintain a straight trajectory when moving up and down, preventing the anchor paddle 3 from deviating and rubbing against the bottom surface of the reactor or creating a dead zone in the stirring. It also prevents the three-bladed paddle 4 from deviating and failing to evenly cover the axial area of ​​the slurry, thus affecting the mixing effect. In addition, this structure can enhance the overall stability of the regulating unit 202, reduce the vibration of the stirring shaft 2 caused by the shaking of the screw 2022 during subsequent stirring operations, and ensure that the anchor paddle 3, the three-bladed paddle 4 and the baffle plate 5 cooperate to form a stable full-range turbulence, providing a uniform and intense mixing environment for the crystallization of SSZ-13 molecular sieves, further avoiding the formation of "a small number of single crystals and large particles" and ensuring the catalytic performance of the molecular sieve.

[0023] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model in any way. Those skilled in the art can readily implement this utility model based on the accompanying drawings and the above description. However, any modifications, alterations, or equivalent variations made by those skilled in the art without departing from the scope of the utility model's technical solution, utilizing the disclosed technical content, are considered equivalent embodiments of this utility model. Furthermore, any equivalent changes, alterations, or variations made to the above embodiments based on the essential technology of this utility model are still within the protection scope of this utility model's technical solution.

Claims

1. A reaction vessel apparatus for molecular sieve crystallization synthesis, characterized in that: include: The reactor body (1) is used to contain molecular sieve crystallization slurry; A stirring shaft (2) is vertically disposed inside the reactor body (1), and the top end of the stirring shaft (2) extends out of the reactor body (1) to connect to the drive mechanism; Anchor (3), the anchor (3) is fixedly installed at the bottom end of the stirring shaft (2), and the anchor (3) is adapted to the inner bottom surface of the reactor body (1) for radial mixing of the crystallized slurry at the bottom of the reactor body (1); The three-bladed paddle (4) is fixedly installed in the area above the anchor paddle (3) of the stirring shaft (2) and is used to axially mix the crystallized slurry in the upper and lower layers of the reactor body (1).

2. The reactor apparatus for molecular sieve crystallization synthesis according to claim 1, characterized in that: A baffle plate (5) is fixedly connected to the inner wall of the reactor body (1). There are four baffle plates (5) in total, and they are evenly distributed along the circumference of the reactor body (1) to make the crystallized slurry bounce during the stirring process to enhance the intensity of stirring.

3. The reactor apparatus for molecular sieve crystallization synthesis according to claim 1, characterized in that: The three blades of the three-bladed impeller (4) are evenly distributed at an angle of 120°, and the plane on which the blades of the three-bladed impeller (4) are located is perpendicular to the axis of the stirring shaft (2).

4. The reactor apparatus for molecular sieve crystallization synthesis according to claim 1, characterized in that: The length of the stirring shaft (2) can be adjusted.

5. The reactor apparatus for molecular sieve crystallization synthesis according to claim 4, characterized in that: The stirring shaft (2) includes a connecting part (201) connected to the drive mechanism. The bottom end of the connecting part (201) is connected to the stirring rod (203) through the adjusting part (202). The anchor paddle (3) and the three-bladed paddle (4) are mounted on the stirring rod (203).

6. The reaction vessel apparatus based on molecular sieve crystallization synthesis according to claim 5, characterized in that: The adjusting part (202) includes a vertical plate (2021) fixed on both sides of the bottom end of the connecting part (201) and a screw (2022) fixed on the top end of the stirring rod (203). A circular plate (2023) is fixedly connected to the bottom end of the vertical plate (2021), and a through hole (20231) for the screw (2022) to pass through is opened in the center of the circular plate (2023). Nuts (2024) are threadedly connected to the outer side wall of the screw (2022) on both the upper and lower sides of the circular plate (2023).

7. The reactor apparatus for molecular sieve crystallization synthesis according to claim 6, characterized in that: Guide rails (2025) are fixedly connected to the opposite surfaces of the two vertical plates (2021), and a top plate (2026) is fixedly connected to the top of the screw (2022). Both sides of the top plate (2026) are slidably connected to the guide rails (2025) via sliders (2027).

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